ACT, in Dramatic Literature, signifies one of those parts into which a play is divided to mark the change of of time or place, and to give a respite to the actors and to the audience. In Greek plays there are no separate acts, the unities being strictly observed, and the action being continuous from beginning to end. If the principal actors left the stage the chorus took up the argument, and contributed an integral part of the play, though chiefly in the form of comment upon the action. When necessary, another drama, which is etymologically the same as an act, carried on the history to a later time or in a different place, and thus we have the Greek trilogies or groups of three dramas, in which the same characters reappear. The Roman poets first adopted the division into acts, and suspended the stage business in the intervals between them. Their number was usually five, and the rule was at last laid down by Horace in the Ars Poetica — “Neve minor, neu sit quinto productior actu Fabula, quae posci vult, et spectata reponi.” “If you would have your play deserve success, Give it five acts complete, nor more nor less.” —Francis....

ACT OF PARLIAMENT. An Act of Parliament may be regarded as a declaration of the Legislature, enforcing certain rules of conduct, or defining rights and conferring them upon or withholding them from certain persons or classes of persons. The collective body of such declarations constitutes the statutes of the realm or written law of the nation, in the widest sense, from Anglo-Saxon times to the present day. It is not, however, till Magna Charta that, in a more limited constitutional sense, the statute-book is generally held to open, and the Parliamentary records only begin to assume distinct outlines late in the reign of Edward I. The maladministration of the common law by the royal judges had gradually taught the people the necessity of obtaining written declarations of their rights—often acknowledged, still oftener violated. Insensibly almost, the Commons, whose chief function it originally was to vote supplies to the crown, began to couple their grants with petitions for the redress of grievances. The substance of these petitions and of the royal responses was in time made the groundwork of Acts which, as framed by court redactors, and appearing annexed to proclamationwrits after the dissolution of Parliament, were frequently found seriously to misrepresent its will. To check this evil an Act was passed (8 Henry IV.), authorising the Commons to be represented at the engrossing of the Parliament roll; but even this surveillance was not enough, for in the beginning of the reign of Henry V. it was enacted, at the instance of the Commons, that in regard to their petitions the royal prerogative should in future be limited to granting or refusing them simpliciter. In this way it became a fixed constitutional principle that an Act of Parliament, to be valid, must express ...

ACT OF SEDERUNT, in Scotch Lazo, an ordinance for regulating the forms of procedure before the Court of Session, passed by the judges in virtue of a power conferred by an Act of the Scotch Parliament, 1540, c. 93. In former times this power was in several instances clearly exceeded, and such Acts of Sederunt required to be ratified by the Scotch Parliament; but for more than a century and a half Acts of Sederunt have been almost exclusively confined to matters relating to the regulation of judicial procedure. Many recent statutes contain a clause empowering the court to make the necessary Acts of Sederunt. A quorum of nine judges is required to pass an Act of Sederunt.

ACTA CONSISTORII, the edicts of the consistory or council of state of the Roman emperors. These edicts were generally expressed in such terms as these: “The august emperors, Diocletian and Maximian, in council declare, That the children of decurions shall not be exposed to wild beasts in the amphitheatre.”—The senate and soldiers often swore, either through flattery or on compulsion, upon the edicts of the emperor. The name of a senator was erased by Nero out of the register, because he refused to swear upon the edicts of Augustus.

ACTA DIURNA, called also Acta Populi, Acta Publica, and simply Acta or Diurna, was a sort of Roman gazette, containing an authorised narrative of the transactions worthy of notice which happened at Rome—as assemblies, edicts of the magistrates, trials, executions, buildings, births, marriages, deaths, accidents, prodigies, &c. Petronius has given us an imitation specimen of the Acta Diurna, one or two extracts from which may be made to show their style and contents. The book-keeper of Trimalchio pretends to read from the Acta Urbis: —“ On the 39th of July, on the Cuman farm, belonging to Trimalchio, were born 30 boys and 40 girls; there were brought into the barn from the threshing-floor 125,000 bushels of wheat; 500 oxen were broken in.—On the same day the slave Mithridates was crucified for having slandered the tutelar deity of our friend Gaius.—On the same day 100,000 sesterces, that could not be invested, were put into the money-box.—On the same day a fire broke out in the gardens of Pompey, which arose in the steward’s house,” &c. The Acta differed from the Annals (which were discontinued in b.c. 133) in this respect, among others, that only the greater and more important matters were given in the latter, while in the former things of less note also were recorded. The origin of the Acta is attributed to Julius Caesar, who first ordered the keeping and publishing of the acts of the people by public officers. Some trace them back as far as Servius Tullius, who it was believed ordered that the next of kin, on occasion of a birth, should register the event in the temple of Venus, and on occasion of a death, should register it in the temple of Libitina. The Acta were drawn up from day to day, and exposed in a public place to be read or copied by all who ...

ACTA SENATUS, among the Romans, were minutes of the discussions and decisions of the senate. These were also called Commentarii Senatus, and, by a Greek name, υπομνήματα. Before the consulship of Julius Caesar, minutes of the proceedings of the senate were written and occasionally published, but unofficially. Caesar first ordered the minutes to be recorded and published authoritatively. The keeping of them was continued by Augustus, but the publication was forbidden. Some prominent senator was usually chosen to draw up these Acta.

ACTIAN GAMES, in Roman Antiquity, solemn games instituted by Augustus, in memory of his victory over Antony at Actium. See Actium.

ACTINIA, a genus of coelenterate animals, of which the sea-anemone is the type. See Actinozoa.

ACTINISM (from ακτίs, a ray), that property of the solar rays whereby they produce chemical effects, as in photography. The actinic force is greatest in the blue and violet rays of the spectrum.